How can some applications still get current application processes and kill them?

Question

How can some applications still get current application processes and kill them?

Background

In the past, I found the following method of killing application background processes, given its package name:

public static boolean killApp(final Context context, final String packageName) { final ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE); final List<ActivityManager.RunningAppProcessInfo> pids = am.getRunningAppProcesses(); for (int i = 0; i < pids.size(); i++) { final ActivityManager.RunningAppProcessInfo info = pids.get(i); if (info.processName.equals(packageName)) { android.os.Process.killProcess(info.pid); if (new File("/system/bin/kill").exists()) { InputStream inputStream = null; try { inputStream = Runtime.getRuntime().exec("kill -9 " + info.pid).getInputStream(); final byte[] buffer = new byte[100]; inputStream.read(buffer); } catch (final IOException e) { } StreamsUtil.closeStream(inputStream); } am.killBackgroundProcesses(packageName); return true; } } am.killBackgroundProcesses(packageName); return false; }

Problem

Since a certain version of Android (5.1), the function for obtaining a list of running processes returns only current application processes, so it is completely useless to use it.

What i found

Most applications on the Play Store do not really display a list of processes, but instead show only the current application process or list of services at best.
It seems that some applications still manage to show the background processes of the applications and even be able to kill them. As an example, I found an AVG app capable of doing this here .
Before they can do this, they tell the user to enable usage statistics for the application, which, as I recall, are used to check general information about the time the applications started.
Another application that has managed to kill background processes, but without any user confirmation, is the " fast task killer ." It also shows a toast of all processes to be killed. I could be wrong, but it seems that there are always as many tasks.
I also think that there is a relatively simple way to get a list of processes using the ps function, but only if the device is deployed (otherwise it will return only the current application processes).
There was a workaround with the library found here (published here ), but this does not seem to work on Android 7.1.2 and most likely in previous versions.